Best Possible World

I'm re-reading Leibniz's Monadology right now and re-thinking about the role some of his principles and concepts have in explaining or illuminating some doctrinal principles. Of course, this is upon interpretation, so please discuss or argue regarding this.

Basically, the concept of a pre-established harmony and the best possible world. I see these as excellent solutions to problem of evil dilemmas and principles to grasp the possibility of omniscience. The problem is how prophesies can direct toward an individual who will apostatize or act in some evil. Assuming that for the plan to be just, every person must have the opportunity for exaltation. There appears to be a contradiction: Person X is prophesied to not receive exaltation, and Person X is required to have the opportunity for exaltation. Now, granted that depending on the interpretation of what it means to be prophesied, the role of knowledge on action, the power of the interaction between personality and situation to derive an outcome, and so on--this might not be an exact contradiction. But, at a simple level: assuming God is omniscient and He placed person X in the place to fulfill the negative prophesy, there appears to be a contradiction. Unless, the place where God put person X was the best possible place for that individual. In other words, the individual by spiritual or natural disposition (or whatever else) would bring upon him or herself the same outcome in every possible situation, but of those possible worlds--God placed person X in the optimal situation for that person, despite the outcome being a fulfillment of a negative prophesy. Hence, the best possible world may have a role in explaining or illuminating doctrine regarding agency, prophesy, and God's omniscience. (On another note, I don't agree with pre-established harmony, but maybe later for that.)

Also, I realize my argument is rough, I'm working at ironing it out and making it more clear, but I figure, it might be better to post and discuss than just hammering at it in my head.